Hunters often use calls to attract game. In recent years diaphragm-type mouth calls have become common. These calls comprise a generally flat horseshoe shaped frame, suspending one or more diaphragms made of latex or the like. The call is placed in the hunter's mouth and, by blowing over the call, the hunter may imitate the call of the prey. The sound produced by the call is determined by the type and number of diaphragms, the shape of the diaphragm, and various types of cuts which are made.
Particularly in the field of turkey hunting, a hunter may wish to carry a wide variety of calls. These calls are used to imitate various sounds made by turkeys, from the calls of a young turkey to those of an old tom or hen. In the past, the hunter would just put the calls in a pocket, and pull them out as needed. If one is trying to call a bird closer, however, that process might cause the hunter to move enough to startle the turkey. Also, it is important to be able to change calls without having to rummage through one's pockets to find the right call, and without removing one's hands from the gun.